Oil scoop duct for rotatable troughed oil pumping drum

ABSTRACT

A scoop duct arrangement for a rotatable troughed oil pumping drum is comprised of a first curved scoop member extending at one end towards the top of the drum in close proximity and substantially tangent to the upper position of the internal floor surface of the trough of the drum in a direction against the direction of rotation of the drum and curved downwards to extend at its other end towards the axis of the drum. The duct further includes an oil distribution member having a surface curving from the other end of the scoop member to incline in the direction of the rotatable axis of the drum towards a bearing lubrication oil port. The mating surfaces at each end of the scoop duct are substantially tangent to the adjacent curved surfaces so that substantially continuous curved surfaces lead to and from the scoop and the oil is scooped and distributed from the drum with a minimum of agitation and aeration. For oil pumping at extremely low speeds, an outer scraper blade is positioned adjacent the upper position of the outer drum floor surface and is angled in the direction of drum rotation towards the distribution member.

iJnited States Patent 1151 3,635,312

Kaufman 1 Jan. 18, 1972 [54] OIL SCOOP DUCT FOR ROTATABLE TROUGHED OIL PUMPING DRUM Primary ExaminerManuel A. Antonakas Attorney-F. H. Henson and F. E. Blake [72] Inventor: Howard N. Kaufman, Monroeville, Pa.

[73] Assignee: Westinghouse Electric Corporation, Pitt- [57] ABSTRACT Sburgh: A scoop duct arrangement for a rotatable troughed oil pump- [22] Filed: July 16, 1970 ing drum is comprised of a first curved scoop member extending at one end towards the top of the drum in close proxlmlty [2]] Appl- No.1 55,313 and substantially tangent to the upper position of the internal floor surface of the trough of the drum in a direction against the direction of rotation of the drum and curved downwards to 'g f ii f extend at its other end towards the axis of the drum. The duct [58] Field ofSearch.... ..l84/6, 6.12, 11, 11 A, 13; dsmbumn membe' havmg F 308/127 128 curving from the other end of the scoop member to lncllne 1n the direction of the rotatable axis of the drum towards a bearing lubrication oil port. The mating surfaces at each end of the [56] References Cited scoop duct are substantially tangent to the adjacent curved n- STATES PATENTS surfaces so that substantially continuous curved surfaces lead to and from the scoop and the oil is scooped and distributed 314765152 1 1/ 1969 Hagg "308/127 from the drum with a minimum of agitation and aeration. For 3,133,222 6/1964 Dames et 1 84/11 A oil pumping at extremely low speeds, an outer scraper blade is 1 2 9/ 1 956 184/612 X positioned adjacent the upper position of the outer drum floor 2,654,441 10/1953 Orr et al. 184/1 1 Surface and is angled in the direction ofdmm rotation mwards 2,536,385 l/i95l Miller 1 84/11 the distribution memben 2,943,517 7/1960 Markley et al.. 3,065,822 l/l962 McAfee ..l84/ll X 3 Claims, 4 Drawing Figures IO F l 'llll l I 4? PMENTEBJAMBWZ 8,635,312

SHEET 1 [IF 2 WITNESSES INVENTOR Howard N. Koufmon %& Z /W MM Y 1 [m1 Y AZTORNEY PATENTEDJAN18I972 3,635,312

sum 2 [1F 2 FIG. 4.

FIGB.

OIL SCOOP DUCT FOR ROTATABLE TROUGHED OIL PUMPING DRUM This invention is an improvement on my copending U.S.

patent application having the same title and filed Mar. 25,

I970, Ser. No. 22,565.

BACKGROUND OF THE INVENTION Self-lubricating bearings having rotatable oil pumping drums for circulating the lubrication oil are well known and reference may be made to the U.S. Pat. No. 3,476,452 issued to Arthur C. Bag and Joseph H. Hoffman on Nov. 4, 1969, for an example of such a bearing construction to which the oil scoop duct of this invention may be applied. It has been found that when the bearing to be lubricated is operating under conditions of high temperature and/or high-rotational shaft speed, the lubricating oil, to be most effective, must be free of bubbles or aeration as may be caused when the oil is agitated. Therefore, a scoop duct for scooping and distributing the oil from a rotatable oil pumping drum should feed the oil smoothly and without agitation or aeration into the bearing lubrication ports. At very low rotational speeds, .the duct must also be effective to distribute an appreciable amount of oil during machinery startup etc.

PRIOR ART SUMMARY In accordance with the present invention, an oil scoop duct for a rotatable troughed oil pumping drum is comprised of a curved scoop member and one curved oil distributing member with the mating surfaces at one end of the scoop duct being substantially tangent to the adjacent internal floor surface of the trough of the drum in its upper position and the mating surfaces at the other end of the scoop being substantially tangent to the curved distributing surface. The; scoop duct is curved to extend at said one end in a direction against the direction of rotation of the oil pumping drum and curves downward at its other end to extend towards the axis of the drum. The oil distributing member is curved to extend from the other end of the scoop duct to incline downwards in the direction of the axis of the drum towards suitable oil distribution ports of the bearing to be lubricated in which is joumaled the rotatable shaft on which the pumping drum is mounted forrotation therewith.

I have found that at very low-rotational speeds, a considerable thickness of oil adheres to the outer drum surface throughout the revolution of the drum. Therefor, an outer scraper member for low-speed oil distributing is positioned adjacent the upper outer drum floor surface and is inclined in the direction of rotation of the drum towards the oil distributing member.

Further details of the invention will be apparent with reference to the following specification and drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a sectional view of the bearing and scoop duct arrangement of the invention;

FIG. 2 is a fragmentary end elevational view of the scoop duct looking into the direction of the inclined oil distributing surface member towards the curved scoop ducts;

FIG. 3 is a top plan view of FIG. 2; and

FIG. 4 is a side elevational view of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 of the drawings, a bearing for which the oil pumping drum and scoop duct of the invention may be used will be briefly described. If a detailed understanding and description of the bearing shown in FIG. 1 is desired, reference should be made to the aforementioned U.S. Pat. No. 3,476,452. The bearing is shown to include a casing'10 having a sump 11 in which a quantity of oil is maintained at all times during operation of the bearing. A rotatable shaft 12 is journaled on sleeve bearing surfaces such as shown at 13-15 and oil is continuously pumped to be distributed through suitable bearing lubrication ports such as shown at 16 and 17 as will be obvious to those skilled in the art. The oil passing through the lubrication ports 16 and 17 is distributed to the requisite bearing surfaces and subsequently is drained-through to accumulate in the sump 11 of the bearing casing 10.

In order to pump the oil from the sump l1 continuously as the shaft 12 rotates for distribution to the bearing lubrication ports such as the port 16, a rotatable oil pumping drum 20 is secured by the hub 21 to the shaft 12 for rotation therewith. The pumping drum 20 is provided with a peripheral trough having an internal trough floor surface 22 together with trough sidewall surfaces 23 and 24. As the troughed pumping drum 20 is rotated, oil within the sump 11-is picked up by the internal trough floor surface 22 of the pumping drum and is carried therewith by centrifugal force and the natural tendency of the oil to cling to a surface as the pumping drum 20 rotates to bring the internal trough floor surface 22 from a lower position to an upper position. Assuming the shaft 12 to be rotating at sufficient speed, with the'pumping drum 20 rotating therewith, a requisite quantity of oil will be picked up from the sump 11 and carried by the floor surface 22 to an upper position where it may be scooped off by the scoop duct 25 to be deposited on the inclined curved surface 31 of the oil distributing member. When the shaft 12 is rotating at extremely low speeds, oil will cling to the outer surface 22a of the drum trough floor 22.

As shown more clearly by FIG. 2 of the drawing, a curved scoop member 25 is curved to extend with one end such as shown at 27 to be substantially tangent to the curved surface of the internal trough floor surface 22 in its upper position. The curved scoop curves downwardly to extend at its other end 29 towards the axis of the pumping drum 20 and shaft 12. Considering the curved scoop duct 25 now being described in detail, it will be noticed that the one end 27 extends in a direction against the counterclockwise direction of rotation of the drum 20 and is therefore effective to scoop oil from the upper floor surface of the trough of the pumping drum when the drum and shaft are rotating in a counterclockwise direction. The other end of the curved scoop duct 25 which is shown at 29 is curved downwards to extend towards the axis of rotation of the pumping drum 20 and shaft 12.

As is more clearly shown by FIGS. 1 and 4 of the drawings, the oil distributing member 31 is provided with a surface curving at its upper end 36 to incline downwardly in the direction of the axis of rotation of the shaft 12 for distributing oil conveyed thereto by the scoop duct 25 to the bearing distribution port 16. It is a particular feature of the invention that the mating surface at the respective end 29 of the scoop duct 25 is substantially tangent with the upper curved surface 36 of the oil distributing member 31. Thus, oil that is scooped by the scoop duct 25 is deposited smoothly upon the oil distributing member 31 and flows with a minimum of agitation and consequent aeration of the oil towards the oil distributing port 16.

As shown more clearly by FIG. 2 of the drawings, the oil distributing member 31 is provided with sidewalls 40 and 41 and is of a width to substantially fill the space between the trough walls of the pumping drum area into which it extends. Thus, the width of the oil distributing member 31 may be said to extend substantially from wall to wall near the top of the troughed rotatable oil pumping drum 20. This is an advantageous feature considering that when shaft 12 is first starting to rotate and the pumping drum 20"consequently is not being rotated at a very high speed, oil carried by the floor 22 of the pumping trough may not cling to the floor for sufficient distance to be engaged by the scoop ends 27 and 28 of the curved scoop members 25 and 26. in such case however, the oil may drop from the floor of the pumping trough upon the floor of oil distributing member 31 before reaching the scraping end 27 of the scoop 25. Thus distribution of some lubricating oil would still be obtained even for low speed rotations of the shaft 12.

However, in accordance with the present invention, oil is distributed at extremely low rotational speeds by the operation of the oil scraper blade 50 which is supported by the bracket 51 affixed to the sidewall 40 of the distributing member 31. It will be noted that the scraper blade 50 is positioned to closely overly without engaging the upper outer surface 22a of the pumping drum in its upper rotational position and is angled in the direction of counterclockwise rotation of the drum towards the distributing member 31 (FIG. 3). The angle should be not greater than 45 as shown for most effective scraping and redirection of the oil clinging to the outer drum surface 220. lf desired, the scraping surface may be formed of a plastic material which, in the event of actual rubbing contact with the drum surface 22a, would provide an effective rubbing surface.

Various modifications will occur to those skilled in the art.

I claim as my invention:

1. in combination with a rotatable troughed oil pumping drum for a self-lubricating bearing, the oil scoop duct arrangement comprising, an oil duct extending from within the drum to a bearing lubrication oil port, said duct having a first curved scoop member extending towards the top of the drum at one end in close proximity and substantially tangent to the internal floor of the troughed surface of the drum in a direction against the direction of rotation of the drum, said first scoop member curving downwards at its other end towards the axis of the drum, said duct further having an oil distributing member with a surface curving from the other end of said first scoop member to incline towards the bearing in alignment with the axis of rotation of the drum to thereby scoop and distribute the oil from the drum to the bearing with a minimum of oil agitation and aeration, said curved scoop surface having an inverted channel shaped cross section with the base of the channel at its one end being closely adjacent the inner floor surface of the trough of the drum, and an oil scraping member positioned closely adjacent the upper position of the outer wall of the drum floor, said scraping member being angled in the direction of rotation of said drum towards said distributing member whereby oil may be scraped from the external floor surface of said drum and flowed onto said distribution member.

2. The invention of claim 1 wherein the mating surfaces at each end of the scoop duct are substantially tangent to the curved surfaces leading to and from.

3. The invention of claim 1 wherein the oil distributing member has a width transverse to the axis of rotation of said drum sufficient to extend substantially from wall to wall near the top of the troughed drum. 

1. In combination with a rotatable troughed oil pumping drum for a self-lubricating bearing, the oil scoop duct arrangement comprising, an oil duct extending from within the drum to a bearing lubrication oil port, said duct having a first curved scoop member extending towards the top of the drum at one end in close proximity and substantially tangent to the internal floor of the troughed surface of the drum in a direction against the direction of rotation of the drum, said first scoop member curving downwards at its other end towards the axis of the drum, said duct further having an oil distributing member with a surface curving from the other end of said first scoop member to incline towards the bearing in aligNment with the axis of rotation of the drum to thereby scoop and distribute the oil from the drum to the bearing with a minimum of oil agitation and aeration, said curved scoop surface having an inverted channel shaped cross section with the base of the channel at its one end being closely adjacent the inner floor surface of the trough of the drum, and an oil scraping member positioned closely adjacent the upper position of the outer wall of the drum floor, said scraping member being angled in the direction of rotation of said drum towards said distributing member whereby oil may be scraped from the external floor surface of said drum and flowed onto said distribution member.
 2. The invention of claim 1 wherein the mating surfaces at each end of the scoop duct are substantially tangent to the curved surfaces leading to and from.
 3. The invention of claim 1 wherein the oil distributing member has a width transverse to the axis of rotation of said drum sufficient to extend substantially from wall to wall near the top of the troughed drum. 